nginx实现负载均衡和健康检查

nginx自带健康检查和负载调度功能，可以通过nginx作为反向代理，通过增加后端服务器来提高性能，用途比较广泛。

安装pcre

1.下载pcer-8.36.tar.gz
2.解压
3.apt-get update
4.apt-get install gcc
5.apt-get install build-essential
6./configure
7.make
8.make install
9.下载nginx
10.apt-get install zlib1g.dev
11../configure
12.make
13.make install

web配置（多台web服务器）
1.apt-get update
2.apt-get install apache2
3.apt-getinstall php5 libapache2-mod-php5
4.cd /etc/apache2
5.vi apache2.conf ,末尾添加 ServerName localhost:80
6.service apache restart
7./var/www/html中添加php文件


配置nginx 
1.echo "/usr/local/lib" >> /etc/ld.so.conf
2.tail -l /etc/ld.so.conf
3.ldconfig
4.cd /usr/local/nginx/conf/
5.mkdir extra
6.vi nginx.conf
7.文件http标签中末尾加上 include extra/upstream01.conf;
8.默认的server删掉,server标签开始往下删
9.vi umstream01.conf,添加如下内容

upstream proxy {
server 10.0.0.17:80 weight=5;
server 10.0.0.18:80 weight=5;
server 10.0.0.19:82 weight=15;
}

server {
listen 80;
server_name blog.etiantian.org;
location / {
proxy_pass http://proxy;
}
}
10.启动nginx